What is the prevalence of coexisting autoimmune disorders in Graves disease?

Boelaert et al investigated the prevalence of and relative risks for coexisting autoimmune diseases in patients with Graves disease (2791 patients) or Hashimoto thyroiditis (495 patients). The authors found coexisting disorders in 9.7% of patients with Graves disease and in 14.3% of those with Hashimoto thyroiditis, with rheumatoid arthritis being the most common of these (prevalence = 3.15% and 4.24% in Graves disease and Hashimoto thyroiditis, respectively). Relative risks of greater than 10 were found for pernicious anemia, systemic lupus erythematosus, Addison disease, celiac disease, and vitiligo. The authors also reported a tendency for parents of patients with Graves disease or Hashimoto thyroiditis to have a history of hyperthyroidism or hypothyroidism, respectively.
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